Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (c) 2000 Markus Friedl. All rights reserved. |
| 3 | * |
| 4 | * Redistribution and use in source and binary forms, with or without |
| 5 | * modification, are permitted provided that the following conditions |
| 6 | * are met: |
| 7 | * 1. Redistributions of source code must retain the above copyright |
| 8 | * notice, this list of conditions and the following disclaimer. |
| 9 | * 2. Redistributions in binary form must reproduce the above copyright |
| 10 | * notice, this list of conditions and the following disclaimer in the |
| 11 | * documentation and/or other materials provided with the distribution. |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 12 | * |
| 13 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| 14 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| 15 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| 16 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 17 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| 18 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 19 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 20 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 21 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| 22 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 23 | */ |
Damien Miller | e4340be | 2000-09-16 13:29:08 +1100 | [diff] [blame] | 24 | |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 25 | #include "includes.h" |
Damien Miller | c5d8635 | 2002-02-05 12:13:41 +1100 | [diff] [blame^] | 26 | RCSID("$OpenBSD: auth2.c,v 1.83 2002/01/29 14:32:03 markus Exp $"); |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 27 | |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 28 | #include <openssl/evp.h> |
| 29 | |
Ben Lindstrom | 226cfa0 | 2001-01-22 05:34:40 +0000 | [diff] [blame] | 30 | #include "ssh2.h" |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 31 | #include "xmalloc.h" |
| 32 | #include "rsa.h" |
Ben Lindstrom | d95c09c | 2001-02-18 19:13:33 +0000 | [diff] [blame] | 33 | #include "sshpty.h" |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 34 | #include "packet.h" |
| 35 | #include "buffer.h" |
Ben Lindstrom | 226cfa0 | 2001-01-22 05:34:40 +0000 | [diff] [blame] | 36 | #include "log.h" |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 37 | #include "servconf.h" |
| 38 | #include "compat.h" |
Ben Lindstrom | c763767 | 2001-06-09 00:36:26 +0000 | [diff] [blame] | 39 | #include "channels.h" |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 40 | #include "bufaux.h" |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 41 | #include "auth.h" |
| 42 | #include "session.h" |
| 43 | #include "dispatch.h" |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 44 | #include "key.h" |
Ben Lindstrom | 6d40c0f | 2001-01-29 09:02:24 +0000 | [diff] [blame] | 45 | #include "cipher.h" |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 46 | #include "kex.h" |
Ben Lindstrom | 226cfa0 | 2001-01-22 05:34:40 +0000 | [diff] [blame] | 47 | #include "pathnames.h" |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 48 | #include "uidswap.h" |
Damien Miller | f6d9e22 | 2000-06-18 14:50:44 +1000 | [diff] [blame] | 49 | #include "auth-options.h" |
Ben Lindstrom | 086cf21 | 2001-03-05 05:56:40 +0000 | [diff] [blame] | 50 | #include "misc.h" |
Ben Lindstrom | 5eabda3 | 2001-04-12 23:34:34 +0000 | [diff] [blame] | 51 | #include "hostfile.h" |
| 52 | #include "canohost.h" |
Ben Lindstrom | 551ea37 | 2001-06-05 18:56:16 +0000 | [diff] [blame] | 53 | #include "match.h" |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 54 | |
| 55 | /* import */ |
| 56 | extern ServerOptions options; |
Ben Lindstrom | 46c1622 | 2000-12-22 01:43:59 +0000 | [diff] [blame] | 57 | extern u_char *session_id2; |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 58 | extern int session_id2_len; |
| 59 | |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 60 | static Authctxt *x_authctxt = NULL; |
| 61 | static int one = 1; |
| 62 | |
| 63 | typedef struct Authmethod Authmethod; |
| 64 | struct Authmethod { |
| 65 | char *name; |
| 66 | int (*userauth)(Authctxt *authctxt); |
| 67 | int *enabled; |
| 68 | }; |
| 69 | |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 70 | /* protocol */ |
| 71 | |
Damien Miller | 630d6f4 | 2002-01-22 23:17:30 +1100 | [diff] [blame] | 72 | static void input_service_request(int, u_int32_t, void *); |
| 73 | static void input_userauth_request(int, u_int32_t, void *); |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 74 | |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 75 | /* helper */ |
Ben Lindstrom | bba8121 | 2001-06-25 05:01:22 +0000 | [diff] [blame] | 76 | static Authmethod *authmethod_lookup(const char *); |
Ben Lindstrom | 7907382 | 2001-07-04 03:42:30 +0000 | [diff] [blame] | 77 | static char *authmethods_get(void); |
Ben Lindstrom | bba8121 | 2001-06-25 05:01:22 +0000 | [diff] [blame] | 78 | static int user_key_allowed(struct passwd *, Key *); |
| 79 | static int hostbased_key_allowed(struct passwd *, const char *, char *, Key *); |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 80 | |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 81 | /* auth */ |
Ben Lindstrom | bba8121 | 2001-06-25 05:01:22 +0000 | [diff] [blame] | 82 | static void userauth_banner(void); |
| 83 | static int userauth_none(Authctxt *); |
| 84 | static int userauth_passwd(Authctxt *); |
| 85 | static int userauth_pubkey(Authctxt *); |
| 86 | static int userauth_hostbased(Authctxt *); |
| 87 | static int userauth_kbdint(Authctxt *); |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 88 | |
| 89 | Authmethod authmethods[] = { |
| 90 | {"none", |
| 91 | userauth_none, |
| 92 | &one}, |
| 93 | {"publickey", |
| 94 | userauth_pubkey, |
Damien Miller | 0bc1bd8 | 2000-11-13 22:57:25 +1100 | [diff] [blame] | 95 | &options.pubkey_authentication}, |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 96 | {"password", |
| 97 | userauth_passwd, |
| 98 | &options.password_authentication}, |
Ben Lindstrom | d1f20ec | 2001-02-10 21:31:53 +0000 | [diff] [blame] | 99 | {"keyboard-interactive", |
| 100 | userauth_kbdint, |
| 101 | &options.kbd_interactive_authentication}, |
Ben Lindstrom | 5eabda3 | 2001-04-12 23:34:34 +0000 | [diff] [blame] | 102 | {"hostbased", |
| 103 | userauth_hostbased, |
| 104 | &options.hostbased_authentication}, |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 105 | {NULL, NULL, NULL} |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 106 | }; |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 107 | |
| 108 | /* |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 109 | * loop until authctxt->success == TRUE |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 110 | */ |
| 111 | |
| 112 | void |
Ben Lindstrom | 3c36bb2 | 2001-12-06 17:55:26 +0000 | [diff] [blame] | 113 | do_authentication2(void) |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 114 | { |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 115 | Authctxt *authctxt = authctxt_new(); |
| 116 | |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 117 | x_authctxt = authctxt; /*XXX*/ |
| 118 | |
Ben Lindstrom | bdfb4df | 2001-10-03 17:12:43 +0000 | [diff] [blame] | 119 | /* challenge-response is implemented via keyboard interactive */ |
Ben Lindstrom | 551ea37 | 2001-06-05 18:56:16 +0000 | [diff] [blame] | 120 | if (options.challenge_response_authentication) |
Ben Lindstrom | 95fb2dd | 2001-01-23 03:12:10 +0000 | [diff] [blame] | 121 | options.kbd_interactive_authentication = 1; |
Damien Miller | f815442 | 2001-04-25 22:44:14 +1000 | [diff] [blame] | 122 | if (options.pam_authentication_via_kbd_int) |
| 123 | options.kbd_interactive_authentication = 1; |
Ben Lindstrom | 95fb2dd | 2001-01-23 03:12:10 +0000 | [diff] [blame] | 124 | |
Damien Miller | 7d05339 | 2002-01-22 23:24:13 +1100 | [diff] [blame] | 125 | dispatch_init(&dispatch_protocol_error); |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 126 | dispatch_set(SSH2_MSG_SERVICE_REQUEST, &input_service_request); |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 127 | dispatch_run(DISPATCH_BLOCK, &authctxt->success, authctxt); |
Ben Lindstrom | b31783d | 2001-03-22 02:02:12 +0000 | [diff] [blame] | 128 | do_authenticated(authctxt); |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 129 | } |
| 130 | |
Ben Lindstrom | bba8121 | 2001-06-25 05:01:22 +0000 | [diff] [blame] | 131 | static void |
Damien Miller | 630d6f4 | 2002-01-22 23:17:30 +1100 | [diff] [blame] | 132 | input_service_request(int type, u_int32_t seq, void *ctxt) |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 133 | { |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 134 | Authctxt *authctxt = ctxt; |
Ben Lindstrom | 46c1622 | 2000-12-22 01:43:59 +0000 | [diff] [blame] | 135 | u_int len; |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 136 | int accept = 0; |
| 137 | char *service = packet_get_string(&len); |
Damien Miller | 48b03fc | 2002-01-22 23:11:40 +1100 | [diff] [blame] | 138 | packet_check_eom(); |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 139 | |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 140 | if (authctxt == NULL) |
| 141 | fatal("input_service_request: no authctxt"); |
| 142 | |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 143 | if (strcmp(service, "ssh-userauth") == 0) { |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 144 | if (!authctxt->success) { |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 145 | accept = 1; |
| 146 | /* now we can handle user-auth requests */ |
| 147 | dispatch_set(SSH2_MSG_USERAUTH_REQUEST, &input_userauth_request); |
| 148 | } |
| 149 | } |
| 150 | /* XXX all other service requests are denied */ |
| 151 | |
| 152 | if (accept) { |
| 153 | packet_start(SSH2_MSG_SERVICE_ACCEPT); |
| 154 | packet_put_cstring(service); |
| 155 | packet_send(); |
| 156 | packet_write_wait(); |
| 157 | } else { |
| 158 | debug("bad service request %s", service); |
| 159 | packet_disconnect("bad service request %s", service); |
| 160 | } |
| 161 | xfree(service); |
| 162 | } |
| 163 | |
Ben Lindstrom | bba8121 | 2001-06-25 05:01:22 +0000 | [diff] [blame] | 164 | static void |
Damien Miller | 630d6f4 | 2002-01-22 23:17:30 +1100 | [diff] [blame] | 165 | input_userauth_request(int type, u_int32_t seq, void *ctxt) |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 166 | { |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 167 | Authctxt *authctxt = ctxt; |
| 168 | Authmethod *m = NULL; |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 169 | char *user, *service, *method, *style = NULL; |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 170 | int authenticated = 0; |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 171 | |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 172 | if (authctxt == NULL) |
| 173 | fatal("input_userauth_request: no authctxt"); |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 174 | |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 175 | user = packet_get_string(NULL); |
| 176 | service = packet_get_string(NULL); |
| 177 | method = packet_get_string(NULL); |
| 178 | debug("userauth-request for user %s service %s method %s", user, service, method); |
Ben Lindstrom | 4dccfa5 | 2000-12-28 16:40:05 +0000 | [diff] [blame] | 179 | debug("attempt %d failures %d", authctxt->attempt, authctxt->failures); |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 180 | |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 181 | if ((style = strchr(user, ':')) != NULL) |
| 182 | *style++ = 0; |
| 183 | |
Kevin Steves | ef4eea9 | 2001-02-05 12:42:17 +0000 | [diff] [blame] | 184 | if (authctxt->attempt++ == 0) { |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 185 | /* setup auth context */ |
| 186 | struct passwd *pw = NULL; |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 187 | pw = getpwnam(user); |
| 188 | if (pw && allowed_user(pw) && strcmp(service, "ssh-connection")==0) { |
| 189 | authctxt->pw = pwcopy(pw); |
| 190 | authctxt->valid = 1; |
| 191 | debug2("input_userauth_request: setting up authctxt for %s", user); |
| 192 | #ifdef USE_PAM |
Damien Miller | 22e22bf | 2001-01-19 15:46:38 +1100 | [diff] [blame] | 193 | start_pam(pw->pw_name); |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 194 | #endif |
| 195 | } else { |
| 196 | log("input_userauth_request: illegal user %s", user); |
Damien Miller | 22e22bf | 2001-01-19 15:46:38 +1100 | [diff] [blame] | 197 | #ifdef USE_PAM |
| 198 | start_pam("NOUSER"); |
| 199 | #endif |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 200 | } |
Ben Lindstrom | c1ba31f | 2001-02-15 03:14:11 +0000 | [diff] [blame] | 201 | setproctitle("%s", pw ? user : "unknown"); |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 202 | authctxt->user = xstrdup(user); |
| 203 | authctxt->service = xstrdup(service); |
Ben Lindstrom | 9d0c066 | 2001-06-09 01:40:00 +0000 | [diff] [blame] | 204 | authctxt->style = style ? xstrdup(style) : NULL; |
| 205 | } else if (strcmp(user, authctxt->user) != 0 || |
| 206 | strcmp(service, authctxt->service) != 0) { |
| 207 | packet_disconnect("Change of username or service not allowed: " |
| 208 | "(%s,%s) -> (%s,%s)", |
| 209 | authctxt->user, authctxt->service, user, service); |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 210 | } |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 211 | /* reset state */ |
Damien Miller | ee11625 | 2001-12-21 12:42:34 +1100 | [diff] [blame] | 212 | auth2_challenge_stop(authctxt); |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 213 | authctxt->postponed = 0; |
Damien Miller | b70b61f | 2000-09-16 16:25:12 +1100 | [diff] [blame] | 214 | |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 215 | /* try to authenticate user */ |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 216 | m = authmethod_lookup(method); |
| 217 | if (m != NULL) { |
| 218 | debug2("input_userauth_request: try method %s", method); |
| 219 | authenticated = m->userauth(authctxt); |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 220 | } |
Damien Miller | 5d57e50 | 2001-03-30 10:48:31 +1000 | [diff] [blame] | 221 | userauth_finish(authctxt, authenticated, method); |
| 222 | |
| 223 | xfree(service); |
| 224 | xfree(user); |
| 225 | xfree(method); |
| 226 | } |
| 227 | |
| 228 | void |
| 229 | userauth_finish(Authctxt *authctxt, int authenticated, char *method) |
| 230 | { |
Ben Lindstrom | cd4349f | 2001-06-09 00:23:17 +0000 | [diff] [blame] | 231 | char *methods; |
| 232 | |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 233 | if (!authctxt->valid && authenticated) |
| 234 | fatal("INTERNAL ERROR: authenticated invalid user %s", |
| 235 | authctxt->user); |
Damien Miller | b70b61f | 2000-09-16 16:25:12 +1100 | [diff] [blame] | 236 | |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 237 | /* Special handling for root */ |
Ben Lindstrom | d8a9021 | 2001-02-15 03:08:27 +0000 | [diff] [blame] | 238 | if (authenticated && authctxt->pw->pw_uid == 0 && |
| 239 | !auth_root_allowed(method)) |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 240 | authenticated = 0; |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 241 | |
| 242 | #ifdef USE_PAM |
Damien Miller | c83de6d | 2001-02-16 14:17:59 +1100 | [diff] [blame] | 243 | if (authenticated && authctxt->user && !do_pam_account(authctxt->user, |
| 244 | NULL)) |
Damien Miller | b70b61f | 2000-09-16 16:25:12 +1100 | [diff] [blame] | 245 | authenticated = 0; |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 246 | #endif /* USE_PAM */ |
| 247 | |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 248 | /* Log before sending the reply */ |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 249 | auth_log(authctxt, authenticated, method, " ssh2"); |
| 250 | |
Ben Lindstrom | cd4349f | 2001-06-09 00:23:17 +0000 | [diff] [blame] | 251 | if (authctxt->postponed) |
| 252 | return; |
| 253 | |
| 254 | /* XXX todo: check if multiple auth methods are needed */ |
| 255 | if (authenticated == 1) { |
| 256 | /* turn off userauth */ |
Damien Miller | 7d05339 | 2002-01-22 23:24:13 +1100 | [diff] [blame] | 257 | dispatch_set(SSH2_MSG_USERAUTH_REQUEST, &dispatch_protocol_ignore); |
Ben Lindstrom | cd4349f | 2001-06-09 00:23:17 +0000 | [diff] [blame] | 258 | packet_start(SSH2_MSG_USERAUTH_SUCCESS); |
| 259 | packet_send(); |
| 260 | packet_write_wait(); |
| 261 | /* now we can break out */ |
| 262 | authctxt->success = 1; |
| 263 | } else { |
Damien Miller | e49d096 | 2001-11-13 23:46:18 +1100 | [diff] [blame] | 264 | if (authctxt->failures++ > AUTH_FAIL_MAX) { |
| 265 | #ifdef WITH_AIXAUTHENTICATE |
| 266 | loginfailed(authctxt->user, |
| 267 | get_canonical_hostname(options.reverse_mapping_check), |
| 268 | "ssh"); |
| 269 | #endif /* WITH_AIXAUTHENTICATE */ |
Ben Lindstrom | cd4349f | 2001-06-09 00:23:17 +0000 | [diff] [blame] | 270 | packet_disconnect(AUTH_FAIL_MSG, authctxt->user); |
Damien Miller | e49d096 | 2001-11-13 23:46:18 +1100 | [diff] [blame] | 271 | } |
Ben Lindstrom | cd4349f | 2001-06-09 00:23:17 +0000 | [diff] [blame] | 272 | methods = authmethods_get(); |
| 273 | packet_start(SSH2_MSG_USERAUTH_FAILURE); |
| 274 | packet_put_cstring(methods); |
| 275 | packet_put_char(0); /* XXX partial success, unused */ |
| 276 | packet_send(); |
| 277 | packet_write_wait(); |
| 278 | xfree(methods); |
| 279 | } |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 280 | } |
| 281 | |
Ben Lindstrom | bba8121 | 2001-06-25 05:01:22 +0000 | [diff] [blame] | 282 | static void |
Ben Lindstrom | 48bd7c1 | 2001-01-09 00:35:42 +0000 | [diff] [blame] | 283 | userauth_banner(void) |
| 284 | { |
| 285 | struct stat st; |
| 286 | char *banner = NULL; |
| 287 | off_t len, n; |
| 288 | int fd; |
| 289 | |
| 290 | if (options.banner == NULL || (datafellows & SSH_BUG_BANNER)) |
| 291 | return; |
Ben Lindstrom | 0cae040 | 2001-04-04 23:47:52 +0000 | [diff] [blame] | 292 | if ((fd = open(options.banner, O_RDONLY)) < 0) |
Ben Lindstrom | 48bd7c1 | 2001-01-09 00:35:42 +0000 | [diff] [blame] | 293 | return; |
Ben Lindstrom | 48bd7c1 | 2001-01-09 00:35:42 +0000 | [diff] [blame] | 294 | if (fstat(fd, &st) < 0) |
| 295 | goto done; |
| 296 | len = st.st_size; |
| 297 | banner = xmalloc(len + 1); |
| 298 | if ((n = read(fd, banner, len)) < 0) |
| 299 | goto done; |
| 300 | banner[n] = '\0'; |
| 301 | packet_start(SSH2_MSG_USERAUTH_BANNER); |
| 302 | packet_put_cstring(banner); |
| 303 | packet_put_cstring(""); /* language, unused */ |
| 304 | packet_send(); |
| 305 | debug("userauth_banner: sent"); |
| 306 | done: |
| 307 | if (banner) |
| 308 | xfree(banner); |
| 309 | close(fd); |
| 310 | return; |
| 311 | } |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 312 | |
Ben Lindstrom | bba8121 | 2001-06-25 05:01:22 +0000 | [diff] [blame] | 313 | static int |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 314 | userauth_none(Authctxt *authctxt) |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 315 | { |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 316 | /* disable method "none", only allowed one time */ |
| 317 | Authmethod *m = authmethod_lookup("none"); |
| 318 | if (m != NULL) |
| 319 | m->enabled = NULL; |
Damien Miller | 48b03fc | 2002-01-22 23:11:40 +1100 | [diff] [blame] | 320 | packet_check_eom(); |
Kevin Steves | ef4eea9 | 2001-02-05 12:42:17 +0000 | [diff] [blame] | 321 | userauth_banner(); |
Damien Miller | b8c656e | 2000-06-28 15:22:41 +1000 | [diff] [blame] | 322 | |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 323 | if (authctxt->valid == 0) |
| 324 | return(0); |
Kevin Steves | ef4eea9 | 2001-02-05 12:42:17 +0000 | [diff] [blame] | 325 | |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 326 | #ifdef HAVE_CYGWIN |
Damien Miller | 0dea79d | 2001-12-29 14:08:28 +1100 | [diff] [blame] | 327 | if (check_nt_auth(1, authctxt->pw) == 0) |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 328 | return(0); |
| 329 | #endif |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 330 | #ifdef USE_PAM |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 331 | return auth_pam_password(authctxt->pw, ""); |
Damien Miller | b8c656e | 2000-06-28 15:22:41 +1000 | [diff] [blame] | 332 | #elif defined(HAVE_OSF_SIA) |
Damien Miller | 92ddb7d | 2001-02-14 01:25:23 +1100 | [diff] [blame] | 333 | return 0; |
Damien Miller | b8c656e | 2000-06-28 15:22:41 +1000 | [diff] [blame] | 334 | #else /* !HAVE_OSF_SIA && !USE_PAM */ |
Damien Miller | 60396b0 | 2001-02-18 17:01:00 +1100 | [diff] [blame] | 335 | return auth_password(authctxt, ""); |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 336 | #endif /* USE_PAM */ |
| 337 | } |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 338 | |
Ben Lindstrom | bba8121 | 2001-06-25 05:01:22 +0000 | [diff] [blame] | 339 | static int |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 340 | userauth_passwd(Authctxt *authctxt) |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 341 | { |
| 342 | char *password; |
| 343 | int authenticated = 0; |
| 344 | int change; |
Ben Lindstrom | 46c1622 | 2000-12-22 01:43:59 +0000 | [diff] [blame] | 345 | u_int len; |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 346 | change = packet_get_char(); |
| 347 | if (change) |
| 348 | log("password change not supported"); |
| 349 | password = packet_get_string(&len); |
Damien Miller | 48b03fc | 2002-01-22 23:11:40 +1100 | [diff] [blame] | 350 | packet_check_eom(); |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 351 | if (authctxt->valid && |
| 352 | #ifdef HAVE_CYGWIN |
Damien Miller | 0dea79d | 2001-12-29 14:08:28 +1100 | [diff] [blame] | 353 | check_nt_auth(1, authctxt->pw) && |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 354 | #endif |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 355 | #ifdef USE_PAM |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 356 | auth_pam_password(authctxt->pw, password) == 1) |
Damien Miller | b8c656e | 2000-06-28 15:22:41 +1000 | [diff] [blame] | 357 | #elif defined(HAVE_OSF_SIA) |
Damien Miller | 92ddb7d | 2001-02-14 01:25:23 +1100 | [diff] [blame] | 358 | auth_sia_password(authctxt->user, password) == 1) |
Damien Miller | b8c656e | 2000-06-28 15:22:41 +1000 | [diff] [blame] | 359 | #else /* !USE_PAM && !HAVE_OSF_SIA */ |
Damien Miller | 60396b0 | 2001-02-18 17:01:00 +1100 | [diff] [blame] | 360 | auth_password(authctxt, password) == 1) |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 361 | #endif /* USE_PAM */ |
| 362 | authenticated = 1; |
| 363 | memset(password, 0, len); |
| 364 | xfree(password); |
| 365 | return authenticated; |
| 366 | } |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 367 | |
Ben Lindstrom | bba8121 | 2001-06-25 05:01:22 +0000 | [diff] [blame] | 368 | static int |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 369 | userauth_kbdint(Authctxt *authctxt) |
| 370 | { |
| 371 | int authenticated = 0; |
Ben Lindstrom | 551ea37 | 2001-06-05 18:56:16 +0000 | [diff] [blame] | 372 | char *lang, *devs; |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 373 | |
| 374 | lang = packet_get_string(NULL); |
| 375 | devs = packet_get_string(NULL); |
Damien Miller | 48b03fc | 2002-01-22 23:11:40 +1100 | [diff] [blame] | 376 | packet_check_eom(); |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 377 | |
Ben Lindstrom | 551ea37 | 2001-06-05 18:56:16 +0000 | [diff] [blame] | 378 | debug("keyboard-interactive devs %s", devs); |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 379 | |
Ben Lindstrom | 551ea37 | 2001-06-05 18:56:16 +0000 | [diff] [blame] | 380 | if (options.challenge_response_authentication) |
Ben Lindstrom | 95fb2dd | 2001-01-23 03:12:10 +0000 | [diff] [blame] | 381 | authenticated = auth2_challenge(authctxt, devs); |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 382 | |
Damien Miller | b848158 | 2000-12-03 11:51:51 +1100 | [diff] [blame] | 383 | #ifdef USE_PAM |
Damien Miller | f815442 | 2001-04-25 22:44:14 +1000 | [diff] [blame] | 384 | if (authenticated == 0 && options.pam_authentication_via_kbd_int) |
Damien Miller | b848158 | 2000-12-03 11:51:51 +1100 | [diff] [blame] | 385 | authenticated = auth2_pam(authctxt); |
| 386 | #endif |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 387 | xfree(devs); |
Ben Lindstrom | 551ea37 | 2001-06-05 18:56:16 +0000 | [diff] [blame] | 388 | xfree(lang); |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 389 | #ifdef HAVE_CYGWIN |
Damien Miller | 0dea79d | 2001-12-29 14:08:28 +1100 | [diff] [blame] | 390 | if (check_nt_auth(0, authctxt->pw) == 0) |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 391 | return(0); |
| 392 | #endif |
| 393 | return authenticated; |
| 394 | } |
| 395 | |
Ben Lindstrom | bba8121 | 2001-06-25 05:01:22 +0000 | [diff] [blame] | 396 | static int |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 397 | userauth_pubkey(Authctxt *authctxt) |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 398 | { |
| 399 | Buffer b; |
| 400 | Key *key; |
| 401 | char *pkalg, *pkblob, *sig; |
Ben Lindstrom | 46c1622 | 2000-12-22 01:43:59 +0000 | [diff] [blame] | 402 | u_int alen, blen, slen; |
Damien Miller | 0bc1bd8 | 2000-11-13 22:57:25 +1100 | [diff] [blame] | 403 | int have_sig, pktype; |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 404 | int authenticated = 0; |
| 405 | |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 406 | if (!authctxt->valid) { |
| 407 | debug2("userauth_pubkey: disabled because of invalid user"); |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 408 | return 0; |
| 409 | } |
| 410 | have_sig = packet_get_char(); |
Ben Lindstrom | d121f61 | 2000-12-03 17:00:47 +0000 | [diff] [blame] | 411 | if (datafellows & SSH_BUG_PKAUTH) { |
| 412 | debug2("userauth_pubkey: SSH_BUG_PKAUTH"); |
| 413 | /* no explicit pkalg given */ |
| 414 | pkblob = packet_get_string(&blen); |
| 415 | buffer_init(&b); |
| 416 | buffer_append(&b, pkblob, blen); |
| 417 | /* so we have to extract the pkalg from the pkblob */ |
| 418 | pkalg = buffer_get_string(&b, &alen); |
| 419 | buffer_free(&b); |
| 420 | } else { |
| 421 | pkalg = packet_get_string(&alen); |
| 422 | pkblob = packet_get_string(&blen); |
| 423 | } |
Damien Miller | 0bc1bd8 | 2000-11-13 22:57:25 +1100 | [diff] [blame] | 424 | pktype = key_type_from_name(pkalg); |
| 425 | if (pktype == KEY_UNSPEC) { |
Ben Lindstrom | d121f61 | 2000-12-03 17:00:47 +0000 | [diff] [blame] | 426 | /* this is perfectly legal */ |
| 427 | log("userauth_pubkey: unsupported public key algorithm: %s", pkalg); |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 428 | xfree(pkalg); |
Ben Lindstrom | d121f61 | 2000-12-03 17:00:47 +0000 | [diff] [blame] | 429 | xfree(pkblob); |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 430 | return 0; |
| 431 | } |
Damien Miller | 0bc1bd8 | 2000-11-13 22:57:25 +1100 | [diff] [blame] | 432 | key = key_from_blob(pkblob, blen); |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 433 | if (key != NULL) { |
| 434 | if (have_sig) { |
| 435 | sig = packet_get_string(&slen); |
Damien Miller | 48b03fc | 2002-01-22 23:11:40 +1100 | [diff] [blame] | 436 | packet_check_eom(); |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 437 | buffer_init(&b); |
Damien Miller | 50a41ed | 2000-10-16 12:14:42 +1100 | [diff] [blame] | 438 | if (datafellows & SSH_OLD_SESSIONID) { |
Damien Miller | 6536c7d | 2000-06-22 21:32:31 +1000 | [diff] [blame] | 439 | buffer_append(&b, session_id2, session_id2_len); |
Damien Miller | 50a41ed | 2000-10-16 12:14:42 +1100 | [diff] [blame] | 440 | } else { |
| 441 | buffer_put_string(&b, session_id2, session_id2_len); |
Damien Miller | 6536c7d | 2000-06-22 21:32:31 +1000 | [diff] [blame] | 442 | } |
Damien Miller | f6d9e22 | 2000-06-18 14:50:44 +1000 | [diff] [blame] | 443 | /* reconstruct packet */ |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 444 | buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST); |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 445 | buffer_put_cstring(&b, authctxt->user); |
Damien Miller | f6d9e22 | 2000-06-18 14:50:44 +1000 | [diff] [blame] | 446 | buffer_put_cstring(&b, |
Ben Lindstrom | d121f61 | 2000-12-03 17:00:47 +0000 | [diff] [blame] | 447 | datafellows & SSH_BUG_PKSERVICE ? |
Damien Miller | f6d9e22 | 2000-06-18 14:50:44 +1000 | [diff] [blame] | 448 | "ssh-userauth" : |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 449 | authctxt->service); |
Ben Lindstrom | d121f61 | 2000-12-03 17:00:47 +0000 | [diff] [blame] | 450 | if (datafellows & SSH_BUG_PKAUTH) { |
| 451 | buffer_put_char(&b, have_sig); |
| 452 | } else { |
| 453 | buffer_put_cstring(&b, "publickey"); |
| 454 | buffer_put_char(&b, have_sig); |
Ben Lindstrom | 3f36496 | 2001-04-19 20:50:07 +0000 | [diff] [blame] | 455 | buffer_put_cstring(&b, pkalg); |
Ben Lindstrom | d121f61 | 2000-12-03 17:00:47 +0000 | [diff] [blame] | 456 | } |
Damien Miller | f6d9e22 | 2000-06-18 14:50:44 +1000 | [diff] [blame] | 457 | buffer_put_string(&b, pkblob, blen); |
Damien Miller | 0bc1bd8 | 2000-11-13 22:57:25 +1100 | [diff] [blame] | 458 | #ifdef DEBUG_PK |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 459 | buffer_dump(&b); |
| 460 | #endif |
| 461 | /* test for correct signature */ |
Damien Miller | 0bc1bd8 | 2000-11-13 22:57:25 +1100 | [diff] [blame] | 462 | if (user_key_allowed(authctxt->pw, key) && |
| 463 | key_verify(key, sig, slen, buffer_ptr(&b), buffer_len(&b)) == 1) |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 464 | authenticated = 1; |
| 465 | buffer_clear(&b); |
| 466 | xfree(sig); |
| 467 | } else { |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 468 | debug("test whether pkalg/pkblob are acceptable"); |
Damien Miller | 48b03fc | 2002-01-22 23:11:40 +1100 | [diff] [blame] | 469 | packet_check_eom(); |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 470 | |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 471 | /* XXX fake reply and always send PK_OK ? */ |
Damien Miller | e247cc4 | 2000-05-07 12:03:14 +1000 | [diff] [blame] | 472 | /* |
| 473 | * XXX this allows testing whether a user is allowed |
| 474 | * to login: if you happen to have a valid pubkey this |
| 475 | * message is sent. the message is NEVER sent at all |
| 476 | * if a user is not allowed to login. is this an |
| 477 | * issue? -markus |
| 478 | */ |
Damien Miller | 0bc1bd8 | 2000-11-13 22:57:25 +1100 | [diff] [blame] | 479 | if (user_key_allowed(authctxt->pw, key)) { |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 480 | packet_start(SSH2_MSG_USERAUTH_PK_OK); |
| 481 | packet_put_string(pkalg, alen); |
| 482 | packet_put_string(pkblob, blen); |
| 483 | packet_send(); |
| 484 | packet_write_wait(); |
Kevin Steves | 4abe4de | 2001-02-08 19:16:32 +0000 | [diff] [blame] | 485 | authctxt->postponed = 1; |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 486 | } |
| 487 | } |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 488 | if (authenticated != 1) |
| 489 | auth_clear_options(); |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 490 | key_free(key); |
| 491 | } |
Damien Miller | 0bc1bd8 | 2000-11-13 22:57:25 +1100 | [diff] [blame] | 492 | debug2("userauth_pubkey: authenticated %d pkalg %s", authenticated, pkalg); |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 493 | xfree(pkalg); |
| 494 | xfree(pkblob); |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 495 | #ifdef HAVE_CYGWIN |
Damien Miller | 0dea79d | 2001-12-29 14:08:28 +1100 | [diff] [blame] | 496 | if (check_nt_auth(0, authctxt->pw) == 0) |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 497 | return(0); |
| 498 | #endif |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 499 | return authenticated; |
| 500 | } |
| 501 | |
Ben Lindstrom | bba8121 | 2001-06-25 05:01:22 +0000 | [diff] [blame] | 502 | static int |
Ben Lindstrom | 5eabda3 | 2001-04-12 23:34:34 +0000 | [diff] [blame] | 503 | userauth_hostbased(Authctxt *authctxt) |
| 504 | { |
| 505 | Buffer b; |
| 506 | Key *key; |
Ben Lindstrom | 671388f | 2001-04-19 20:40:45 +0000 | [diff] [blame] | 507 | char *pkalg, *pkblob, *sig, *cuser, *chost, *service; |
Ben Lindstrom | 5eabda3 | 2001-04-12 23:34:34 +0000 | [diff] [blame] | 508 | u_int alen, blen, slen; |
| 509 | int pktype; |
| 510 | int authenticated = 0; |
| 511 | |
| 512 | if (!authctxt->valid) { |
| 513 | debug2("userauth_hostbased: disabled because of invalid user"); |
| 514 | return 0; |
| 515 | } |
| 516 | pkalg = packet_get_string(&alen); |
| 517 | pkblob = packet_get_string(&blen); |
| 518 | chost = packet_get_string(NULL); |
| 519 | cuser = packet_get_string(NULL); |
| 520 | sig = packet_get_string(&slen); |
| 521 | |
| 522 | debug("userauth_hostbased: cuser %s chost %s pkalg %s slen %d", |
| 523 | cuser, chost, pkalg, slen); |
| 524 | #ifdef DEBUG_PK |
| 525 | debug("signature:"); |
| 526 | buffer_init(&b); |
| 527 | buffer_append(&b, sig, slen); |
| 528 | buffer_dump(&b); |
| 529 | buffer_free(&b); |
| 530 | #endif |
| 531 | pktype = key_type_from_name(pkalg); |
| 532 | if (pktype == KEY_UNSPEC) { |
| 533 | /* this is perfectly legal */ |
| 534 | log("userauth_hostbased: unsupported " |
| 535 | "public key algorithm: %s", pkalg); |
| 536 | goto done; |
| 537 | } |
| 538 | key = key_from_blob(pkblob, blen); |
| 539 | if (key == NULL) { |
| 540 | debug("userauth_hostbased: cannot decode key: %s", pkalg); |
| 541 | goto done; |
| 542 | } |
Ben Lindstrom | 671388f | 2001-04-19 20:40:45 +0000 | [diff] [blame] | 543 | service = datafellows & SSH_BUG_HBSERVICE ? "ssh-userauth" : |
| 544 | authctxt->service; |
Ben Lindstrom | 5eabda3 | 2001-04-12 23:34:34 +0000 | [diff] [blame] | 545 | buffer_init(&b); |
Ben Lindstrom | 671388f | 2001-04-19 20:40:45 +0000 | [diff] [blame] | 546 | buffer_put_string(&b, session_id2, session_id2_len); |
Ben Lindstrom | 5eabda3 | 2001-04-12 23:34:34 +0000 | [diff] [blame] | 547 | /* reconstruct packet */ |
| 548 | buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST); |
| 549 | buffer_put_cstring(&b, authctxt->user); |
Ben Lindstrom | 671388f | 2001-04-19 20:40:45 +0000 | [diff] [blame] | 550 | buffer_put_cstring(&b, service); |
Ben Lindstrom | 5eabda3 | 2001-04-12 23:34:34 +0000 | [diff] [blame] | 551 | buffer_put_cstring(&b, "hostbased"); |
| 552 | buffer_put_string(&b, pkalg, alen); |
| 553 | buffer_put_string(&b, pkblob, blen); |
| 554 | buffer_put_cstring(&b, chost); |
| 555 | buffer_put_cstring(&b, cuser); |
| 556 | #ifdef DEBUG_PK |
| 557 | buffer_dump(&b); |
| 558 | #endif |
| 559 | /* test for allowed key and correct signature */ |
| 560 | if (hostbased_key_allowed(authctxt->pw, cuser, chost, key) && |
| 561 | key_verify(key, sig, slen, buffer_ptr(&b), buffer_len(&b)) == 1) |
| 562 | authenticated = 1; |
| 563 | |
| 564 | buffer_clear(&b); |
| 565 | key_free(key); |
| 566 | |
| 567 | done: |
| 568 | debug2("userauth_hostbased: authenticated %d", authenticated); |
| 569 | xfree(pkalg); |
| 570 | xfree(pkblob); |
| 571 | xfree(cuser); |
| 572 | xfree(chost); |
| 573 | xfree(sig); |
| 574 | return authenticated; |
| 575 | } |
| 576 | |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 577 | /* get current user */ |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 578 | |
| 579 | struct passwd* |
| 580 | auth_get_user(void) |
| 581 | { |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 582 | return (x_authctxt != NULL && x_authctxt->valid) ? x_authctxt->pw : NULL; |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 583 | } |
| 584 | |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 585 | #define DELIM "," |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 586 | |
Ben Lindstrom | 7907382 | 2001-07-04 03:42:30 +0000 | [diff] [blame] | 587 | static char * |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 588 | authmethods_get(void) |
| 589 | { |
| 590 | Authmethod *method = NULL; |
Damien Miller | 0e3b872 | 2002-01-22 23:26:38 +1100 | [diff] [blame] | 591 | Buffer b; |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 592 | char *list; |
| 593 | |
Damien Miller | 0e3b872 | 2002-01-22 23:26:38 +1100 | [diff] [blame] | 594 | buffer_init(&b); |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 595 | for (method = authmethods; method->name != NULL; method++) { |
| 596 | if (strcmp(method->name, "none") == 0) |
| 597 | continue; |
| 598 | if (method->enabled != NULL && *(method->enabled) != 0) { |
Damien Miller | 0e3b872 | 2002-01-22 23:26:38 +1100 | [diff] [blame] | 599 | if (buffer_len(&b) > 0) |
| 600 | buffer_append(&b, ",", 1); |
| 601 | buffer_append(&b, method->name, strlen(method->name)); |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 602 | } |
| 603 | } |
Damien Miller | 0e3b872 | 2002-01-22 23:26:38 +1100 | [diff] [blame] | 604 | buffer_append(&b, "\0", 1); |
| 605 | list = xstrdup(buffer_ptr(&b)); |
| 606 | buffer_free(&b); |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 607 | return list; |
| 608 | } |
| 609 | |
Ben Lindstrom | bba8121 | 2001-06-25 05:01:22 +0000 | [diff] [blame] | 610 | static Authmethod * |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 611 | authmethod_lookup(const char *name) |
| 612 | { |
| 613 | Authmethod *method = NULL; |
| 614 | if (name != NULL) |
| 615 | for (method = authmethods; method->name != NULL; method++) |
| 616 | if (method->enabled != NULL && |
| 617 | *(method->enabled) != 0 && |
| 618 | strcmp(name, method->name) == 0) |
| 619 | return method; |
| 620 | debug2("Unrecognized authentication method name: %s", name ? name : "NULL"); |
| 621 | return NULL; |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 622 | } |
| 623 | |
| 624 | /* return 1 if user allows given key */ |
Ben Lindstrom | bba8121 | 2001-06-25 05:01:22 +0000 | [diff] [blame] | 625 | static int |
Ben Lindstrom | f96704d | 2001-06-25 04:17:12 +0000 | [diff] [blame] | 626 | user_key_allowed2(struct passwd *pw, Key *key, char *file) |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 627 | { |
Ben Lindstrom | f96704d | 2001-06-25 04:17:12 +0000 | [diff] [blame] | 628 | char line[8192]; |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 629 | int found_key = 0; |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 630 | FILE *f; |
Ben Lindstrom | 46c1622 | 2000-12-22 01:43:59 +0000 | [diff] [blame] | 631 | u_long linenum = 0; |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 632 | struct stat st; |
| 633 | Key *found; |
Damien Miller | da9edca | 2001-12-21 12:48:54 +1100 | [diff] [blame] | 634 | char *fp; |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 635 | |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 636 | if (pw == NULL) |
| 637 | return 0; |
| 638 | |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 639 | /* Temporarily use the user's uid. */ |
Ben Lindstrom | 3fcf1a2 | 2001-04-08 18:26:59 +0000 | [diff] [blame] | 640 | temporarily_use_uid(pw); |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 641 | |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 642 | debug("trying public key file %s", file); |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 643 | |
| 644 | /* Fail quietly if file does not exist */ |
| 645 | if (stat(file, &st) < 0) { |
| 646 | /* Restore the privileged uid. */ |
| 647 | restore_uid(); |
| 648 | return 0; |
| 649 | } |
| 650 | /* Open the file containing the authorized keys. */ |
| 651 | f = fopen(file, "r"); |
| 652 | if (!f) { |
| 653 | /* Restore the privileged uid. */ |
| 654 | restore_uid(); |
| 655 | return 0; |
| 656 | } |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 657 | if (options.strict_modes && |
Ben Lindstrom | 90279d8 | 2001-07-04 03:56:56 +0000 | [diff] [blame] | 658 | secure_filename(f, file, pw, line, sizeof(line)) != 0) { |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 659 | fclose(f); |
| 660 | log("Authentication refused: %s", line); |
| 661 | restore_uid(); |
| 662 | return 0; |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 663 | } |
Ben Lindstrom | bfb3a0e | 2001-06-05 20:25:05 +0000 | [diff] [blame] | 664 | |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 665 | found_key = 0; |
Damien Miller | d344494 | 2000-09-30 14:20:03 +1100 | [diff] [blame] | 666 | found = key_new(key->type); |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 667 | |
| 668 | while (fgets(line, sizeof(line), f)) { |
Damien Miller | f6d9e22 | 2000-06-18 14:50:44 +1000 | [diff] [blame] | 669 | char *cp, *options = NULL; |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 670 | linenum++; |
| 671 | /* Skip leading whitespace, empty and comment lines. */ |
| 672 | for (cp = line; *cp == ' ' || *cp == '\t'; cp++) |
| 673 | ; |
| 674 | if (!*cp || *cp == '\n' || *cp == '#') |
| 675 | continue; |
Damien Miller | f6d9e22 | 2000-06-18 14:50:44 +1000 | [diff] [blame] | 676 | |
Ben Lindstrom | 1bc3bdb | 2001-09-20 23:11:26 +0000 | [diff] [blame] | 677 | if (key_read(found, &cp) != 1) { |
Damien Miller | f6d9e22 | 2000-06-18 14:50:44 +1000 | [diff] [blame] | 678 | /* no key? check if there are options for this key */ |
| 679 | int quoted = 0; |
Damien Miller | 0bc1bd8 | 2000-11-13 22:57:25 +1100 | [diff] [blame] | 680 | debug2("user_key_allowed: check options: '%s'", cp); |
Damien Miller | f6d9e22 | 2000-06-18 14:50:44 +1000 | [diff] [blame] | 681 | options = cp; |
| 682 | for (; *cp && (quoted || (*cp != ' ' && *cp != '\t')); cp++) { |
| 683 | if (*cp == '\\' && cp[1] == '"') |
| 684 | cp++; /* Skip both */ |
| 685 | else if (*cp == '"') |
| 686 | quoted = !quoted; |
| 687 | } |
| 688 | /* Skip remaining whitespace. */ |
| 689 | for (; *cp == ' ' || *cp == '\t'; cp++) |
| 690 | ; |
Ben Lindstrom | 1bc3bdb | 2001-09-20 23:11:26 +0000 | [diff] [blame] | 691 | if (key_read(found, &cp) != 1) { |
Damien Miller | 0bc1bd8 | 2000-11-13 22:57:25 +1100 | [diff] [blame] | 692 | debug2("user_key_allowed: advance: '%s'", cp); |
Damien Miller | f6d9e22 | 2000-06-18 14:50:44 +1000 | [diff] [blame] | 693 | /* still no key? advance to next line*/ |
| 694 | continue; |
| 695 | } |
| 696 | } |
| 697 | if (key_equal(found, key) && |
Ben Lindstrom | 226cfa0 | 2001-01-22 05:34:40 +0000 | [diff] [blame] | 698 | auth_parse_options(pw, options, file, linenum) == 1) { |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 699 | found_key = 1; |
Ben Lindstrom | 940fb86 | 2001-08-06 21:01:49 +0000 | [diff] [blame] | 700 | debug("matching key found: file %s, line %lu", |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 701 | file, linenum); |
Damien Miller | da9edca | 2001-12-21 12:48:54 +1100 | [diff] [blame] | 702 | fp = key_fingerprint(found, SSH_FP_MD5, SSH_FP_HEX); |
| 703 | verbose("Found matching %s key: %s", |
Damien Miller | 9f0f5c6 | 2001-12-21 14:45:46 +1100 | [diff] [blame] | 704 | key_type(found), fp); |
Damien Miller | da9edca | 2001-12-21 12:48:54 +1100 | [diff] [blame] | 705 | xfree(fp); |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 706 | break; |
| 707 | } |
| 708 | } |
| 709 | restore_uid(); |
| 710 | fclose(f); |
| 711 | key_free(found); |
Ben Lindstrom | b54873a | 2001-03-11 20:01:55 +0000 | [diff] [blame] | 712 | if (!found_key) |
| 713 | debug2("key not found"); |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 714 | return found_key; |
| 715 | } |
Ben Lindstrom | 5eabda3 | 2001-04-12 23:34:34 +0000 | [diff] [blame] | 716 | |
Ben Lindstrom | f96704d | 2001-06-25 04:17:12 +0000 | [diff] [blame] | 717 | /* check whether given key is in .ssh/authorized_keys* */ |
Ben Lindstrom | bba8121 | 2001-06-25 05:01:22 +0000 | [diff] [blame] | 718 | static int |
Ben Lindstrom | f96704d | 2001-06-25 04:17:12 +0000 | [diff] [blame] | 719 | user_key_allowed(struct passwd *pw, Key *key) |
| 720 | { |
| 721 | int success; |
| 722 | char *file; |
| 723 | |
| 724 | file = authorized_keys_file(pw); |
| 725 | success = user_key_allowed2(pw, key, file); |
| 726 | xfree(file); |
| 727 | if (success) |
| 728 | return success; |
| 729 | |
| 730 | /* try suffix "2" for backward compat, too */ |
| 731 | file = authorized_keys_file2(pw); |
| 732 | success = user_key_allowed2(pw, key, file); |
| 733 | xfree(file); |
| 734 | return success; |
| 735 | } |
| 736 | |
Ben Lindstrom | 5eabda3 | 2001-04-12 23:34:34 +0000 | [diff] [blame] | 737 | /* return 1 if given hostkey is allowed */ |
Ben Lindstrom | bba8121 | 2001-06-25 05:01:22 +0000 | [diff] [blame] | 738 | static int |
Ben Lindstrom | 4aa603c | 2001-04-19 20:38:06 +0000 | [diff] [blame] | 739 | hostbased_key_allowed(struct passwd *pw, const char *cuser, char *chost, |
Ben Lindstrom | 5eabda3 | 2001-04-12 23:34:34 +0000 | [diff] [blame] | 740 | Key *key) |
| 741 | { |
Ben Lindstrom | 5eabda3 | 2001-04-12 23:34:34 +0000 | [diff] [blame] | 742 | const char *resolvedname, *ipaddr, *lookup; |
Ben Lindstrom | 65366a8 | 2001-12-06 16:32:47 +0000 | [diff] [blame] | 743 | HostStatus host_status; |
| 744 | int len; |
Ben Lindstrom | 5eabda3 | 2001-04-12 23:34:34 +0000 | [diff] [blame] | 745 | |
Damien Miller | c5d8635 | 2002-02-05 12:13:41 +1100 | [diff] [blame^] | 746 | resolvedname = get_canonical_hostname(options.verify_reverse_mapping); |
Ben Lindstrom | 5eabda3 | 2001-04-12 23:34:34 +0000 | [diff] [blame] | 747 | ipaddr = get_remote_ipaddr(); |
| 748 | |
Ben Lindstrom | 2bffd6f | 2001-04-19 20:35:40 +0000 | [diff] [blame] | 749 | debug2("userauth_hostbased: chost %s resolvedname %s ipaddr %s", |
| 750 | chost, resolvedname, ipaddr); |
Ben Lindstrom | 5eabda3 | 2001-04-12 23:34:34 +0000 | [diff] [blame] | 751 | |
| 752 | if (options.hostbased_uses_name_from_packet_only) { |
| 753 | if (auth_rhosts2(pw, cuser, chost, chost) == 0) |
| 754 | return 0; |
| 755 | lookup = chost; |
| 756 | } else { |
Ben Lindstrom | 2bffd6f | 2001-04-19 20:35:40 +0000 | [diff] [blame] | 757 | if (((len = strlen(chost)) > 0) && chost[len - 1] == '.') { |
| 758 | debug2("stripping trailing dot from chost %s", chost); |
| 759 | chost[len - 1] = '\0'; |
| 760 | } |
Ben Lindstrom | 5eabda3 | 2001-04-12 23:34:34 +0000 | [diff] [blame] | 761 | if (strcasecmp(resolvedname, chost) != 0) |
| 762 | log("userauth_hostbased mismatch: " |
| 763 | "client sends %s, but we resolve %s to %s", |
| 764 | chost, ipaddr, resolvedname); |
| 765 | if (auth_rhosts2(pw, cuser, resolvedname, ipaddr) == 0) |
| 766 | return 0; |
| 767 | lookup = resolvedname; |
| 768 | } |
| 769 | debug2("userauth_hostbased: access allowed by auth_rhosts2"); |
| 770 | |
Ben Lindstrom | 83647ce | 2001-06-25 04:30:16 +0000 | [diff] [blame] | 771 | host_status = check_key_in_hostfiles(pw, key, lookup, |
| 772 | _PATH_SSH_SYSTEM_HOSTFILE, |
Ben Lindstrom | a4789ef | 2001-06-25 04:40:49 +0000 | [diff] [blame] | 773 | options.ignore_user_known_hosts ? NULL : _PATH_SSH_USER_HOSTFILE); |
Ben Lindstrom | 5eabda3 | 2001-04-12 23:34:34 +0000 | [diff] [blame] | 774 | |
Ben Lindstrom | 83647ce | 2001-06-25 04:30:16 +0000 | [diff] [blame] | 775 | /* backward compat if no key has been found. */ |
| 776 | if (host_status == HOST_NEW) |
| 777 | host_status = check_key_in_hostfiles(pw, key, lookup, |
| 778 | _PATH_SSH_SYSTEM_HOSTFILE2, |
Ben Lindstrom | a4789ef | 2001-06-25 04:40:49 +0000 | [diff] [blame] | 779 | options.ignore_user_known_hosts ? NULL : |
| 780 | _PATH_SSH_USER_HOSTFILE2); |
Ben Lindstrom | 5eabda3 | 2001-04-12 23:34:34 +0000 | [diff] [blame] | 781 | |
Ben Lindstrom | 5eabda3 | 2001-04-12 23:34:34 +0000 | [diff] [blame] | 782 | return (host_status == HOST_OK); |
| 783 | } |
Ben Lindstrom | 83647ce | 2001-06-25 04:30:16 +0000 | [diff] [blame] | 784 | |